It would not be surprising if ancient life did exist on Mars, since impacts would likely have sent life back and forth between Earth and Mars (and possibly Venus).
For the same reason, the existence of ancient life on Mars would not show that life is likely to arise on Earth-like worlds, since one could not conclude it was an independent event.
That is the question, yes. But if lithopanspermia is a thing, we don't need to go to Mars to investigate that question: we can look for this variant biochemistry life right here on Earth. This sounds to me like a valuable and economical research effort.
>impacts would likely have sent life back and forth between Earth and Mars
By what mechanism is an impact giving some debris on Mars enough delta-V to reach Earth, without obliterating Mars and also sterilizing the debris due to heat and plasma?
When the strong shock wave generated in rock by an impact hits a rock/atmosphere (or rock/vacuum) surface, it is reflected, producing strong tensile stress. This causes very large acceleration while not subjecting the spalled layer to extreme temperature or pressure.
This is the same process that HESH (High Explosive Squash Head) antitank rounds use to defeat tank armor without penetration. The explosive squashes against the armor before detonating, launching a shock through it causing material to spall off the inner surface at high speed. The shock here is weaker than in the impact case, however.
while that's possible, it's also likely to burn the hell out of anything in / on / around.
any would-be hitchhikers would need to be able to survive extinction-ish level impacts on Mars, survive through the vacuum (e.g. months), and then survive atmospheric re-entry and landing.
Certainly a great deal of energy is released. However, on the time scale of an impact, heat doesn't diffuse in rock very far. Even on the time scale of reentry to an atmosphere heat doesn't diffuse far. It's common for a meteorite that has fallen to Earth, despite the surface having been melted and ablated, to have an inside that is still freezing cold.
Ah, this was the piece I was missing. I assumed the heat of impact and/or re-entry would sterilize just about anything that wasn't an engineered heat shield.
The concern in the impact is how much heat is produced in the material itself, by the shock wave. A shock wave is dissipative, producing entropy and heat as it propagates, but near the spalled surface it cancels itself out and the heating becomes small.
chunks get blasted off essentialy whole and
unmodified, as they are contained in bigger chunks that act asl launch shields, though will exerience truely massive acceleration and then renentry on earth and other bodies.
The evidence for life on mars is based on carbon nodules in rock, and things like CO² and methane gas,and some other chemistry and mineralology.
The main one are the carbon nodules, which are ubiquitous in many sedimentary rocks on earth, though in the samples that I have of earth rocks, there are very often macro fossils that are naked eye identifiable There are countless miles of cliff here where everything has a fossil, but complete specimins, and soft tissue fossils remain rare, here, so the chances of such a thing making it to earth from mars, schould it exist in the first place are almost zero, though the martian ice caps could concievably hold meteors with earth life fossils that are naked eye visible and identifiable.
The article is good but the title is a bit too slippery a statement in my opinion. The article is saying more evidence is consistent with possible ancient life on Mars. In astrobiology the massive problem is that geology can imitate biology. The presences of minerals formed by microbes on Earth does not prove microbes are involved in their production on Mars, it is a big jump to make.
We have long passed at least my owner personal "threshold of evidence" to assume that Mars had life.
That bar is pretty low. I am not hard to convince.
We don't have a baseline by which to contextualize the situation statistically. There is no p-value we can meaningfully satisfy. Worse than that, evidence required for a belief derives from the risk of being wrong.
Is there a discussion of what evidence WOULD be enough for the scientific community to say loudly "There was life on mars". Because right now it seems all risk and no utility, so the evidence bar would be really high.
The bar for scientific discoveries is generally incredibly high and rightly so. In particle physics for example for a discovery to be confirmed it must be independently verified by a second experiment and both the discovering experiment and confirming experiment must be within five standard deviations (or a roughly 1 in 3.5 million) chance of not being a discovery. Its not a perfect comparison because astrobiology is messier but it is useful to see how high the bar is.
For a discovery of the magnitude of life outside our planet the scientific community would probably need something like: a real and well-characterised signal, multiple independent lines of evidence, strong geological context, replication by independent teams, and a serious failure of plausible alternate explanations. Until then, “potential biosignature” is probably the right phrase.
To be clear, I think like you that there probably was life at some point on Mars. I am pretty convinced. But, you and I being pretty convinced does not come close to the threshold of a scientific discovery.
Tangential, but really looking forward to what Europa Clipper[0] finds in its flybys.
The delay in communication makes ambitious manoeuvres challenging - perhaps advances in AI (and by extension robotics) helps build much more autonomous space rovers. This could enable us, for example, to evaluate the samples by sending wet microscopes with the rover itself.
I am not an astrophysicist, but I have read that the thick layer of ice is supposed to protect the miles-deep ocean against radiation, which might harbour life.
The era of AI makes me realize that if we ever get visited by aliens: it will probably not be actual aliens -- just an AI probe. And the idea of it really intrigues me.
Imagine some LLM that is many generations ahead of Fable -- but from a different world -- visiting us. It would be amazing. And it would likely be better at figuring out how to communicate with us (than the human-equivalent might).
Some of the more out there UFO theories postulate on these lines. An idea that rather than say send an explorer of your own species to some planet with all the needed life support, you use genetic engineering to create a worker bee essentially, already tailored to perform whatever function under whatever environmental conditions are present at the target planet. You may even be able to build this species using genes already present at the host system in some reduced to essential components fashion like an engineered plasmid in the molecular biology lab. This would also double as camouflage keeping the worker bee genetics separate from genetics found in your own planet or star system, making them appear endogenous to the target planet instead.
> Imagine some LLM that is many generations ahead of Fable -- but from a different world -- visiting us. It would be amazing.
Why? Why would you expect it to be any more benevolent or any less murderous than the actual aliens visiting? Presumably it would be trained on their values, not ours.
I wouldn't expect it to be less murderous than the aliens themselves. That wasn't my point at all. I'd expect it to contain all their knowledge and be able to live "forever".
But I generally wouldn't expect aliens to be "murderous" at all. Why send a group or probe lightyears away just to kill or enslave a primitive species? If they have the ability to do that, we wouldn't really have anything of interest for them.
At most points in time resources are scarce and not all life can be supported. At those times beings with a tendency to say “them” will give way to beings who most strongly assert “us”.
Comments like yours make me think that sci-fi shows (and a lot of literary sci-fi) like Star Trek did a grave disservice to our conception of advanced spacefaring civilizations. They were always focused on alien planets, assuming that once a race was able to travel the stars that they would still chain themselves to a gravity well. It's like imagining an industrial society where everyone still lives on a farm like their agricultural predecessors. Nothing makes sense if you start with that assumption, living space becomes scarce, utilities are hard to provide, travel is cumbersome and a lot of things simply aren't possible. The same way that industrial societies urbanized and concentrated in cities, spacefaring civilizations will move to orbital structures that allow them to design their environments. These may be located near planets the same way cities are located near important geographical features but there will also be many that are only in orbit around their host star. Habitable worlds will become the equivalent of bucolic countryside estates or national parks. Most industry will be located around lesser gravity wells such as moons or minor planets where mined materials are easy to transport to orbit and there aren't biospheres or atmospheres to worry about. It would take a long time and a lot of expansion to exhaust the materials in a solar system.
“You mean we all came from Earth?” said Nikolai, unbelieving. “Yes,” the holo said kindly. “The first true settlers in space were born on Earth—produced by sexual means. Of course, hundreds of years have passed since then. You are a Shaper. Shapers are never born.” “Who lives on Earth now?” “Human beings.” “Ohhhh,” said Nikolai, his falling tones betraying a rapid loss of interest. --- Twenty Evocations (1984) Bruce Sterling
In his novel Aurora, Kim Stanley Robinson challenged this view by suggesting that at the small scale of orbital structures, there may be insurmountable obstacles to biological life, like the buildup of salt through waste. His ultimate conclusion was that “life is a planetary phenomenon” (and we should take better care of the planet we have).
If I remember correctly, the novel was concerned with a generation ship travelling to a distant star. This is not the same as space habitats in a solar system where there are plenty of sources and sinks for all materials involved in the maintenance of a habitat.
I think he modeled his habitats as large ecosystems as well in the novel. That's not strictly necessary and would simplify the design a lot.
Also, it was a fictional story so not the best source for information. Which is kind of proving my point about sci-fi messing up everyone's conception of what the future could hold.
The scarcity view of life is so deeply ingrained in some of us that its become an entire world view. Some folks cant even imagine a post scarcity society.
Try though. Space is mind blowingly large and anything with the ability to traverse interstellar space alteady has access to unlimited resources and energy, likely closer than us. We live in a tiny backwater of the galaxy.
We literally have nothing of value to such a civilization. Gold and diamonds a just more rocks to any serious space faring civilizations. Energy is also unlimited and free.
Unless they find us delicious our only value would likely be an exchange of knowledge.
Some sci fi author (I forget who) pointed out that in a space faring society, the most valuable materials are biological materials. Once you have access to comets and planets, you'll have, for all intents and purposes, an infinite supply of gold, diamond, ruby, etc.
Wood however... You're not gonna find a lot of wood in space.
There is absolutely no reason for alien life to have evolved the same biological materials that we have. But also, a space faring species that can build an AI probe capable of remaining functioning for the many years an interstellar journey takes, is also likely to be capable of building habitats that can grow their biological materials. It'd be much easier than shipping those materials over from another star.
Yep. It's all about mass at those scales. There will never be a time when it makes sense to ship giant habitats full of water, and oxygen, and meat around.
Brains will be uploaded to machines, or human descended AI's will will be built and tasked with exploring the places it's unsafe or too time consuming for us to visit directly. The square jawed men with laser guns will have to stay at home and watch. Maybe those AI's will be built to start cloning humans once they find a good spot or something, but it's never going to make sense to ship squishy meat sacks and the metric tons of accoutrements required to keep them alive all over unless/until we find a way around the speed of light or perfect hibernation.
Quite right! They probably wouldn't have wood, but we do!
They might want the wood though, and they might not know how to grow it. From there we can see 2 scenarios. The likelier one hopefully being trade: we could probably teach them to grow wood, and also provide them with seeds, perhaps on exchange for some of their space-faring tech.
Alternatively there's the pessimist scenario, where they're not interested in trading for it, we're not willing to give it freely, and so war ensues.
Personally I'd just give them a few pine-cones and explain basic horticulture as a gesture of good faith, I guess the end result is rather contingent on which human they talk to.
Why would they need our permission to take it? They can grab the seeds from anywhere on the planet, and they can just watch any farmer and/or forest for a couple of years and see how it works.
Of course this is putting aside any ideas of deciphering our books or tapping into the internet. Not much we'd be able to do to species that can travel the stars.
> Why send a group or probe lightyears away just to kill or enslave a primitive species?
Killing/enslavement just as a side effect. You have to tell it explicitly to NOT kill/enslave covering any edge cases. Even if they do we can turn out to be sufficiently different that the probe doesn't consider us relevant from aliens' standpoint.
> Why send a group or probe lightyears away just to kill or enslave a primitive species?
That question makes no sense. It presumes that they are at all interested in, or even notice, us. We're special, from our PoV. That doesn't mean we are special.
Did you notice how many ants you drove over on your last car trip? Did you even care?
To a space-faring species, we are probably just as interesting as ants. After all, you are assuming that they'll send their brightest minds to visit us, but it is equally likely that we are "discovered" by their equivalent of joy-riding teens.
Our values are murderous, I wouldn't want to be visited by aliens that shared out values. A galactic version of human society would quite reasonably identify that earth couldn't fight back then special interests would have our planet liquidated for its natural resources without making headlines in space-news. Possibly colonise us, kill all the humans then offer an apology a few generations later and maybe a small local holiday to commemorate the process.
Regardless, there aren't that many possible values aliens could have. It is hard to come up with something outside basic game theory - you can see how most religions tend to converge on the same practical principles over time, like basic property rights and not causing trouble pointlessly.
I don't see why an intelligent alien species would have similar values to us. It would depend entirely on their social organization so unless they were the exact equivalent of us evolutionarily (omnivorous, sexually dimorphic, social, bipedal, terrestrial, etc.) they would value the lives, property, territory and status of their own kind and other animals very differently.
A race of aquatic arthropods could be mostly solitary, cannibalistic and regard age and size as primary dominance characteristics and their notion of property rights might depend entirely on whether they can eat the owner of said property, though sublimated through some complex set of social rules and protocols. Maybe the CEO of a company only has to offer a single leg to be eaten during a hostile takeover.
A necessary condition for the emergence of civilization (in its broadest sense, as in the collectively organized reshaping of one's living environment for one's purposes) is a basic level of trust and cooperation.
Humans are not naturally prone to bouts of violence like other species and human societies do not tolerate impulsive violence in adults. Instead, the vast majority of human-on-human violence is deliberate: people plan, carefully and rationally, the killing of their fellow human beings in order to achieve their goals. This is known as 'war'. This is very rare among species, and more violent species cannot form complex societies at scale, despite being also quite smart in some cases (chimps, octopuses).
We even unconsciously internalized this idea to some degree, since most people are comfortable with the idea of militaries existing and being necessary but also agree that solitary murderous psychopaths should be put in prison.
I mean could a race of aquatic arthropods ever organize in scale enough to be a species that can travel light years and invade others? Wouldn't they just eat each other and never have any need to build a community or to colonize space?
We need to have some baseline for what we consider as "intelligent species" in this context and most intelligent species will need to have a system where they can pool their resources together towards something in a sustained social manner. This rules out a lot of social patterns such as beings that are solitary, canibalisitc and hell bent of eating each other.
If you showed me a primate and I didn't have any knowledge of the existence of humans and then asked the same thing of them I'd also have to get creative about how they may evolve to be an intelligent society.
I spent ages trying to find it, but couldn't. Unless I dreamed it.
I read a sci-fi story where the probe lands on Earth, and then teaches us enough science to get our own ships together, and tells us where to go to meet the probe makers. So they don't have to go anywhere and can sit comfortable at home and wait for the aliens to come to them.
NASA intentionally completely gave up on trying to answer the Mars life question for multiple decades and only very recently has come back around to the idea of doing life finding missions.
It's a touchy subject because scientists are afraid of looking like cranks. Just like cognition in other nonhuman species was historically dismissed because no one wants to be seen as someone who think plants talk to each other
We all came from Mars, don't you know it? There was a series of "extreme weather events" and we had to escape. Now there is some guy dreaming to get back home. /s
I see this author has "12 honorary degrees and is an Officer of the Order of Canada". And CBC is Canada's government-funded national public broadcaster.
But it's hard to take them seriously on any particular details given that their article, up for 8+ months (!), mis-describes H.G. Wells' War of the Worlds as a story of the Earth "invaded by benevolent Martians". [emphasis mine]
It's a seminal work of scifi, which popularized the "alien invasion" genre and term "Martians' (both for literal creatures from Mars and also a metonym for any alien visitors/invaders). It's been adapted to film many times. And the Martians in it - with their disintegrating heat-rays & death-clouds, consuming human blood – are far from 'benevolent'.
It was obviously meant to read 'malevolent' and got spell checked to death. That sort of thing happens to everyone, and I'm not sure why you mention the authors credentials like they're a bad thing?
But that's obviously not a reason to treat them as a bad thing. It's also not entirely true ... he was awarded those honors because of the quality of his science journalism.
FWIW, I think @mapontosevenths is wrong to say that @gojomo's mention of the honorary degrees and being an OOC was "like they're a bad thing" ... their "But it's hard ..." indicates a conflict between those "credentials" and the typo that gojomo makes way too much a deal of.
So many people here have no idea how things work and are far more interested in virtue signaling over an error (and making spiteful downvotes) than in correcting it, so we get ignorant and intellectually dishonest rubbish like
> I think readers should take this as an illustrative example of how often people/institutions draped in such quasi-credentials are carelessly wrong on basic things.
and
> how many people had to be asleep at the wheel for the truth-reversing error to get published, & persist for months? Does no one at the CBC – with pride in its work & any familiarity with these topics – read CBC's slop?
I, OTOH, sent them a note and they quickly fixed the article. Errors like this "persist for months" simply because no one takes the time for such a simple action when they encounter an error ... I'm the only person among those who commented here who did so. And no, of course no one at the CBC or anywhere else spends their time rereading their months-old articles to see if some error made its way in.
Because I think readers should take this as an illustrative example of how often people/institutions draped in such quasi-credentials are carelessly wrong on basic things.
Even if some typo of 'malevolent' becoming 'benevolent' was how this error initially created – & I have my doubts! – how many people had to be asleep at the wheel for the truth-reversing error to get published, & persist for months? Does no one at the CBC – with pride in its work & any familiarity with these topics – read CBC's slop?
I got so caught up in that phrase I went rereading the plot summary of WOTW to check my memory. After than I had no interest in the article, assuming it had been written by AI.
War of the Worlds is culturally-prominent enough I doubt any commercial AI would make this same mistake (or let the error slip through, if they'd asked the AI to fact-check the article).
Maybe the author mixed it up, with another Martin invasion story called "Two Planets" (https://en.wikipedia.org/wiki/Two_Planets), which was released a bit earlier than War of the Worlds and according to Wikipedia, it "is the earliest known example of the theme of a Beneficial alien invasion".
If someone is interested in "historical" science fiction, I can recommend it.
But nonetheless, if the author is interested in Mars and science fiction, he should be able to keep them apart from another. Maybe an editor wasn't?
It's hard to take seriously someone who dismisses the (factually correct) content of a popular science article just because of a typo that has no bearing on that content.
Have you independently checked all the other allegedly "factually correct" info in this article, with other sources that are actually diligent in getting the details right? What's the incremental value of a news source where every detail that you don't already know might be very wrong?
Italian. Maybe their browser auto translates English to Italian and expects everyone else to have a browser functioning that way (translating any to their native language)?
Mineral that can be only formed by life, or under special conditions when water flows over rock, has been found on Mars, where water had been known to flow over rock.
NASA doesn't want to find life on Mars. They want to find evidence, so that the next probe can be more complex and more expensive than the previous one.
NASA will never send wet microscope to Mars, you know, the kind you used in school to show bacteria in dirty water. As that would instantly prove life on Mars and make ever more expensive probes hard to justify.
I’m curious why you seem to believe that all exploration of Mars would cease as soon as life is discovered there? It would be one of the biggest scientific discoveries of all time and would open up a huge number of possible future missions, for the next few centuries at least. It would also make for good justification for missions to other worlds that could harbor life.
Weak evidence for life, at best. Which is why exploration continues, to search for stronger evidence. If irrefutable evidence of life were found it would open up many new avenues of exploration and research that would need funding, with strong justification - much stronger justification than currently exists.
I don't think it was weak at all. We got two positive results from the Viking landers and then tried to explain them away. There is a lot of circumstantial evidence, which combined builds up a case.
The public believe we should be looking for cities and skeletons, when in fact we should be looking for extremophiles. It is possible that some of these are due to cross-contamination within the solar system (before human intervention), but that is another matter.
They are best thought of as circumstantial evidence, especially when combined with the various other possible indicators we have detected on Mars. Many books I have read over the years talk about the Viking experiments as if they had disproved life, whereas they did no such thing.
However, I think the bulk of life on Mars – if it exists – is probably underground. Conditions there are much less hostile than the immediate surface. Since Viking, we continue to find Earth life in extreme environments including high altitudes and deep underground. Microbes can be much tougher than animals.
The two Viking landers, 6500km apart, had positive results. That would suggest that life is widespread and close to the surface. But the atmosphere of Mars is in chemical equilibrium, which means life can't be widespread and close to the surface because it is not affecting the atmosphere. If life is present on Mars it would have to be deep underground, perhaps in a geothermally heated brine lake, which would be very hard to detect with current technology. The Viking data was probably non-biological, it really isn't strong evidence for life today.
There are questions about methane in the Martian atmosphere. Again, there is some ambiguity as to why.
However, we have found life in some very hostile environments on Earth, notably high up in the atmosphere. Planococcus halocryophilus can exist on Earth at -20' C, well within Martian surface temperature ranges, and is tolerant of very salty water. Microbes need a fraction of the resources we do, and some can exist in very small numbers for long periods before better conditions come along. Surface temperatures on Mars have been observed to go over 20' C during the day in some places which may allow for some warmth to penetrate rock and dust. A very hostile environment, to be sure.
Sending a microscope is easier said than done. Many natural structures can look like bacteria, and vice versa. If there's more complex single celled life then we might see stuff swimming around but that's considered unlikely close to the surface where there's a decent amount of solar and cosmic radiation. If complex life does exist it's probably deep underground or in caves and lava tubes where we can't reach it yet.
The other reason is planetary protection. The best places to send a microscope are low lying areas where there may be brines near the surface. Those specific areas have been designated high on the list of protection sites. Earth microbes are really resilient, so even with intense sterilization procedures we can't be 100% sure. We don't want to contaminate the most valuable scientific find ever, and so we're approaching it carefully.
But I think the first reason I gave is the most significant one. It's technically pretty hard and not definitive. The surface of Mars is probably mostly sterile even if there is life. If it survives, it's probably underground.
I also disagree that NASA would not want to find life. If anything, finding life would make their budget explode. They could suddenly make a strong case for a Europa submersible, a submarine to visit Titan's methane lakes, huge space-based SETI radio telescope arrays, huge space telescopes to try to find more exoplanets and characterize their atmospheres, all kinds of things, since we'd know for a fact there's life out there.
If life emerged in two places in one solar system, we'd know that the universe is teeming with it. Maybe not complex intelligent life -- there's still reasons to think Earth may be kind of special for that. But life, certainly.
Luna is abrasive, essentially like shards of non safety glass. The dust on mars is soft, it's been blowing around since before the dinosaurs died off. The main issue with martian dust is electrostatic charge, but that's easier to manage than lunar dust.
I think the opposite - unless the discovery of life was preceeded or coincidental with the discovery of some other hyper interesting thing (for example, if Martian life has some sort of utility for medicine, maybe) then I think that would be that for Mars exploration missions. Of course there would be many announcements and excited political agreements around "continuing to explore the new frontier" but I think that no more money would appear.
I suspect that NASA knows this full well, as do Mars scientists, and I suspect that they are being very careful to make sure that definitive proof does not appear until they understand all sorts of other stuff about the planet.
But why? Why would there be no money for that but there’s money now when there’s no conclusive evidence of life, past or present, on Mars? It makes no sense.
If life were found on Mars then the greatest mystery of our time would be whether life originated at least twice independently, or if we share a common origin. Both of which have significant implications, to put it mildly.
Well, Viking carried an experiment that tried to detect life. Now, the consensus is that it failed, and that the experiment was incapable of creating a useful result given the chemistry of the soil. Some people argue about that, but I am in no way qualified to take part in the debate, so I would back the consensus here.
What is odd is that there hasn't been a single other mission that's carried any experiment that has the objective of creating that result.
If the objective is to find life, why isn't anyone actually looking?
Tell me if what I've said above is in any way factually incorrect.
The Viking results were at worst, inconclusive and at best positive. And yet in both cases we have been led to believe they were negative. They are far from the only pointers to life on Mars either, since we've seen pictures of what look like fossilised stromatolites and algal mats, seasonal methane emissions, and discolorations in seasonal flows & ice.
Even the rusty coloured surface of Mars may be due, in part, to organic oxidisation processes.
We aren't talking about Richard Hoagland style cities here (although that Face on Mars is a lot less easy to explain away that some people claim).
The “face on mars” is an image compression artefact that disappeared as soon as they had high resolution imaging of the area. Seeing it as a face is highly dependent on sympathetic lighting and the right time of day, like lots of similar features on earth eg the “Old Man” of Hoy which I have seen first-hand and you really have to want to see it as a man’s face to do so https://en.wikipedia.org/wiki/Cydonia_(Mars)
I've heard this before and the pareidolia argument. The fact remains that in certain other pictures you still can see the face. There are some other unusual formations near it as well. The only example that comes close is the Badlands Indian in North America.
I've always found it an extremely weird formation. I suppose it has been explained by frost shattering and ancient floods. If an ancient race were to leave sculpture behind, millions of years would obliterate most of it. Some people have said that probes should be sent to Cydonia. I hope they send some kind of flying probes round there, since the geology alone makes it of interest, and landers/orbiters may not get it.
As for the Old Man of Hoy, that is something different. Old Man (or Bodach in Gaelic speaking areas) was used for a lot of natural pillars and stacks, standing stones and phallic formations. Occasionally for mountains. Old Man/Bodach is/was a euphemism for the Devil who was said to have created many of these things, and that goes way back before the Old Man of Hoy.
In Gaelic, it takes on a phallic quality: "Bod" means "penis" and "bodach" means "old man". Orkney was never Gaelic speaking as such, but in Gaelic the euphemism is more obvious. This usage carried over there and the Old Man of Hoy probably gets that name because it is tall and thin. Maybe the Picts had such notions too.
You have to admire the discipline, willpower, and solidarity of all those scientists. Any one of them could prove the existence of life on Mars at any time, win a Nobel Prize, become the the most famous scientist since Einstein, put themselves on the gravy train for life... but they all hold out, keeping their decent, upper-middle class jobs, hiding one of the greatest discoveries in history, so that their colleagues don't have to find potentially slightly less lucrative or interesting jobs. That's dedication!
>>Well, Viking carried an experiment that tried to detect life. Now, the consensus is that it failed, and that the experiment was incapable of creating a useful result given the chemistry of the soil. Some people argue about that, but I am in no way qualified to take part in the debate, so I would back the consensus here.
>>What is odd is that there hasn't been a single other mission that's carried any experiment that has the objective of creating that result.
>>If the objective is to find life, why isn't anyone actually looking?
>>Tell me if what I've said above is in any way factually incorrect.
So... you tell me. Why no experiment? Not one in 50 years?
In the meantime we've learned a lot about the Martian atmosphere, it's climate, it's history, it's geology, the evolution of it's surface. I would argue that if a Viking 3 had flown with a revised kit that produced a definitive signal we wouldn't have got any of that.
This is an odd comment. Any scientist or scientific organisation would love to be the first to discover life on another planet. It would catapult that organisation and individuals involved to legendary status with their discoveries being counted amongst the greatest of humankind. It would be an epoch defining moment. Funding for their work and personal riches would pour in. There would be movies made about it. Their names would be remembered thousands of years into the future.
To imply there would be a conspiracy to cover up such discoveries because you think the opposite would happen is such an odd way to think about things.
Do you really think that all the scientists view NASA as a make work program? That so many people spent years in schools getting advanced degrees and there is no one there who wants to make the most significant discovery in the history of humanity? That nobody wants the instant Nobel prize?
It also doesn't make sense from any kind of financial perspective. The budget for NASA would explode for all kinds of missions. They would have free reign to go wherever and do anything.
The discovery team would instantly create brand new fields of study and career paths, and anyone on the team that discovered life would become experts in the field with unlimited investment opportunities to continue their research.
Viking 1 & 2 returned positive results in the seventies but these have been played down or hand waved. I think there is good evidence of microbial life in the soil or underground. We should be wary of bringing Martian microbes back to Earth, because they may find our environment too hospitable and end up invasive species.
Yes, that is perfectly possible. There could be some transfer, but there is a scenario where Martian microbes breed on Earth and have no natural controls. An Australia type scenario on a planetary scale.
>..War of the Worlds, where Earth is invaded by benevolent Martians.
I don't think I have heard the word benevolent used in that context before.
Hopefully, that was a dictation error and Bob McDonald actually said "malevolent". Either that or the CBC editors got a hold of it.
They came to serve man.
Well done.
Brilliant.
Maybe benevolent in the same way a heat-ray is a form of urban renewal
Did AI write it? If so that is concerning...
No, Martians wrote it as counter propaganda
It would not be surprising if ancient life did exist on Mars, since impacts would likely have sent life back and forth between Earth and Mars (and possibly Venus).
For the same reason, the existence of ancient life on Mars would not show that life is likely to arise on Earth-like worlds, since one could not conclude it was an independent event.
In some ways the more interesting question might become whether Martian life, if found, shares the same basic biochemistry as Earth life
That is the question, yes. But if lithopanspermia is a thing, we don't need to go to Mars to investigate that question: we can look for this variant biochemistry life right here on Earth. This sounds to me like a valuable and economical research effort.
>impacts would likely have sent life back and forth between Earth and Mars
By what mechanism is an impact giving some debris on Mars enough delta-V to reach Earth, without obliterating Mars and also sterilizing the debris due to heat and plasma?
It's surprising but it's a real thing: https://en.wikipedia.org/wiki/Martian_meteorite
> By what mechanism.
Impact spallation.
When the strong shock wave generated in rock by an impact hits a rock/atmosphere (or rock/vacuum) surface, it is reflected, producing strong tensile stress. This causes very large acceleration while not subjecting the spalled layer to extreme temperature or pressure.
This is the same process that HESH (High Explosive Squash Head) antitank rounds use to defeat tank armor without penetration. The explosive squashes against the armor before detonating, launching a shock through it causing material to spall off the inner surface at high speed. The shock here is weaker than in the impact case, however.
while that's possible, it's also likely to burn the hell out of anything in / on / around.
any would-be hitchhikers would need to be able to survive extinction-ish level impacts on Mars, survive through the vacuum (e.g. months), and then survive atmospheric re-entry and landing.
and then be able to survive in the new ecosystem
Certainly a great deal of energy is released. However, on the time scale of an impact, heat doesn't diffuse in rock very far. Even on the time scale of reentry to an atmosphere heat doesn't diffuse far. It's common for a meteorite that has fallen to Earth, despite the surface having been melted and ablated, to have an inside that is still freezing cold.
Ah, this was the piece I was missing. I assumed the heat of impact and/or re-entry would sterilize just about anything that wasn't an engineered heat shield.
The concern in the impact is how much heat is produced in the material itself, by the shock wave. A shock wave is dissipative, producing entropy and heat as it propagates, but near the spalled surface it cancels itself out and the heating becomes small.
chunks get blasted off essentialy whole and unmodified, as they are contained in bigger chunks that act asl launch shields, though will exerience truely massive acceleration and then renentry on earth and other bodies.
The evidence for life on mars is based on carbon nodules in rock, and things like CO² and methane gas,and some other chemistry and mineralology. The main one are the carbon nodules, which are ubiquitous in many sedimentary rocks on earth, though in the samples that I have of earth rocks, there are very often macro fossils that are naked eye identifiable There are countless miles of cliff here where everything has a fossil, but complete specimins, and soft tissue fossils remain rare, here, so the chances of such a thing making it to earth from mars, schould it exist in the first place are almost zero, though the martian ice caps could concievably hold meteors with earth life fossils that are naked eye visible and identifiable.
The article is good but the title is a bit too slippery a statement in my opinion. The article is saying more evidence is consistent with possible ancient life on Mars. In astrobiology the massive problem is that geology can imitate biology. The presences of minerals formed by microbes on Earth does not prove microbes are involved in their production on Mars, it is a big jump to make.
Let's use your sentence in place of the title above. Thanks!
Classic dang.
We have long passed at least my owner personal "threshold of evidence" to assume that Mars had life.
That bar is pretty low. I am not hard to convince.
We don't have a baseline by which to contextualize the situation statistically. There is no p-value we can meaningfully satisfy. Worse than that, evidence required for a belief derives from the risk of being wrong.
Is there a discussion of what evidence WOULD be enough for the scientific community to say loudly "There was life on mars". Because right now it seems all risk and no utility, so the evidence bar would be really high.
The bar for scientific discoveries is generally incredibly high and rightly so. In particle physics for example for a discovery to be confirmed it must be independently verified by a second experiment and both the discovering experiment and confirming experiment must be within five standard deviations (or a roughly 1 in 3.5 million) chance of not being a discovery. Its not a perfect comparison because astrobiology is messier but it is useful to see how high the bar is.
For a discovery of the magnitude of life outside our planet the scientific community would probably need something like: a real and well-characterised signal, multiple independent lines of evidence, strong geological context, replication by independent teams, and a serious failure of plausible alternate explanations. Until then, “potential biosignature” is probably the right phrase.
To be clear, I think like you that there probably was life at some point on Mars. I am pretty convinced. But, you and I being pretty convinced does not come close to the threshold of a scientific discovery.
We can say we discovered signs there might've once been life on Mars
What I like about Mars stories like this is that they are a good antidote to both extremes: "we found life!" and "there is nothing interesting here"
Tangential, but really looking forward to what Europa Clipper[0] finds in its flybys.
The delay in communication makes ambitious manoeuvres challenging - perhaps advances in AI (and by extension robotics) helps build much more autonomous space rovers. This could enable us, for example, to evaluate the samples by sending wet microscopes with the rover itself.
[0]: https://science.nasa.gov/mission/europa-clipper/
Too much radiation for anything close to Jupiter. You will find life on Venus clouds and in Titan....
Everybody looking at the wrong targets. Mars is a dead, radiation cooked, burned, poisonous place. Forget about it, leave it to the trillionaires.
> Too much radiation for anything close to Jupiter.
Europa's water is an excellent radiation shield.
I am not an astrophysicist, but I have read that the thick layer of ice is supposed to protect the miles-deep ocean against radiation, which might harbour life.
Tangential to your tangential:
The era of AI makes me realize that if we ever get visited by aliens: it will probably not be actual aliens -- just an AI probe. And the idea of it really intrigues me.
Imagine some LLM that is many generations ahead of Fable -- but from a different world -- visiting us. It would be amazing. And it would likely be better at figuring out how to communicate with us (than the human-equivalent might).
We need some new sci fi movies like that!
Some of the more out there UFO theories postulate on these lines. An idea that rather than say send an explorer of your own species to some planet with all the needed life support, you use genetic engineering to create a worker bee essentially, already tailored to perform whatever function under whatever environmental conditions are present at the target planet. You may even be able to build this species using genes already present at the host system in some reduced to essential components fashion like an engineered plasmid in the molecular biology lab. This would also double as camouflage keeping the worker bee genetics separate from genetics found in your own planet or star system, making them appear endogenous to the target planet instead.
> Imagine some LLM that is many generations ahead of Fable -- but from a different world -- visiting us. It would be amazing.
Why? Why would you expect it to be any more benevolent or any less murderous than the actual aliens visiting? Presumably it would be trained on their values, not ours.
I wouldn't expect it to be less murderous than the aliens themselves. That wasn't my point at all. I'd expect it to contain all their knowledge and be able to live "forever".
But I generally wouldn't expect aliens to be "murderous" at all. Why send a group or probe lightyears away just to kill or enslave a primitive species? If they have the ability to do that, we wouldn't really have anything of interest for them.
At most points in time resources are scarce and not all life can be supported. At those times beings with a tendency to say “them” will give way to beings who most strongly assert “us”.
Comments like yours make me think that sci-fi shows (and a lot of literary sci-fi) like Star Trek did a grave disservice to our conception of advanced spacefaring civilizations. They were always focused on alien planets, assuming that once a race was able to travel the stars that they would still chain themselves to a gravity well. It's like imagining an industrial society where everyone still lives on a farm like their agricultural predecessors. Nothing makes sense if you start with that assumption, living space becomes scarce, utilities are hard to provide, travel is cumbersome and a lot of things simply aren't possible. The same way that industrial societies urbanized and concentrated in cities, spacefaring civilizations will move to orbital structures that allow them to design their environments. These may be located near planets the same way cities are located near important geographical features but there will also be many that are only in orbit around their host star. Habitable worlds will become the equivalent of bucolic countryside estates or national parks. Most industry will be located around lesser gravity wells such as moons or minor planets where mined materials are easy to transport to orbit and there aren't biospheres or atmospheres to worry about. It would take a long time and a lot of expansion to exhaust the materials in a solar system.
“You mean we all came from Earth?” said Nikolai, unbelieving. “Yes,” the holo said kindly. “The first true settlers in space were born on Earth—produced by sexual means. Of course, hundreds of years have passed since then. You are a Shaper. Shapers are never born.” “Who lives on Earth now?” “Human beings.” “Ohhhh,” said Nikolai, his falling tones betraying a rapid loss of interest. --- Twenty Evocations (1984) Bruce Sterling
In his novel Aurora, Kim Stanley Robinson challenged this view by suggesting that at the small scale of orbital structures, there may be insurmountable obstacles to biological life, like the buildup of salt through waste. His ultimate conclusion was that “life is a planetary phenomenon” (and we should take better care of the planet we have).
If I remember correctly, the novel was concerned with a generation ship travelling to a distant star. This is not the same as space habitats in a solar system where there are plenty of sources and sinks for all materials involved in the maintenance of a habitat.
I think he modeled his habitats as large ecosystems as well in the novel. That's not strictly necessary and would simplify the design a lot.
Also, it was a fictional story so not the best source for information. Which is kind of proving my point about sci-fi messing up everyone's conception of what the future could hold.
Living in bunkers is no fun, I love cities but even those are bigger than the best generation ship.
In his novel Aurora, Kim Stanley Robinson challenged the view that works of fiction should be well written and function as entertainment.
The scarcity view of life is so deeply ingrained in some of us that its become an entire world view. Some folks cant even imagine a post scarcity society.
Try though. Space is mind blowingly large and anything with the ability to traverse interstellar space alteady has access to unlimited resources and energy, likely closer than us. We live in a tiny backwater of the galaxy.
We literally have nothing of value to such a civilization. Gold and diamonds a just more rocks to any serious space faring civilizations. Energy is also unlimited and free.
Unless they find us delicious our only value would likely be an exchange of knowledge.
Some sci fi author (I forget who) pointed out that in a space faring society, the most valuable materials are biological materials. Once you have access to comets and planets, you'll have, for all intents and purposes, an infinite supply of gold, diamond, ruby, etc.
Wood however... You're not gonna find a lot of wood in space.
There is absolutely no reason for alien life to have evolved the same biological materials that we have. But also, a space faring species that can build an AI probe capable of remaining functioning for the many years an interstellar journey takes, is also likely to be capable of building habitats that can grow their biological materials. It'd be much easier than shipping those materials over from another star.
Yep. It's all about mass at those scales. There will never be a time when it makes sense to ship giant habitats full of water, and oxygen, and meat around.
Brains will be uploaded to machines, or human descended AI's will will be built and tasked with exploring the places it's unsafe or too time consuming for us to visit directly. The square jawed men with laser guns will have to stay at home and watch. Maybe those AI's will be built to start cloning humans once they find a good spot or something, but it's never going to make sense to ship squishy meat sacks and the metric tons of accoutrements required to keep them alive all over unless/until we find a way around the speed of light or perfect hibernation.
Quite right! They probably wouldn't have wood, but we do!
They might want the wood though, and they might not know how to grow it. From there we can see 2 scenarios. The likelier one hopefully being trade: we could probably teach them to grow wood, and also provide them with seeds, perhaps on exchange for some of their space-faring tech.
Alternatively there's the pessimist scenario, where they're not interested in trading for it, we're not willing to give it freely, and so war ensues.
Personally I'd just give them a few pine-cones and explain basic horticulture as a gesture of good faith, I guess the end result is rather contingent on which human they talk to.
Why would they need our permission to take it? They can grab the seeds from anywhere on the planet, and they can just watch any farmer and/or forest for a couple of years and see how it works.
Of course this is putting aside any ideas of deciphering our books or tapping into the internet. Not much we'd be able to do to species that can travel the stars.
> Why send a group or probe lightyears away just to kill or enslave a primitive species?
Killing/enslavement just as a side effect. You have to tell it explicitly to NOT kill/enslave covering any edge cases. Even if they do we can turn out to be sufficiently different that the probe doesn't consider us relevant from aliens' standpoint.
> Why send a group or probe lightyears away just to kill or enslave a primitive species?
That question makes no sense. It presumes that they are at all interested in, or even notice, us. We're special, from our PoV. That doesn't mean we are special.
Did you notice how many ants you drove over on your last car trip? Did you even care?
To a space-faring species, we are probably just as interesting as ants. After all, you are assuming that they'll send their brightest minds to visit us, but it is equally likely that we are "discovered" by their equivalent of joy-riding teens.
Our values are murderous, I wouldn't want to be visited by aliens that shared out values. A galactic version of human society would quite reasonably identify that earth couldn't fight back then special interests would have our planet liquidated for its natural resources without making headlines in space-news. Possibly colonise us, kill all the humans then offer an apology a few generations later and maybe a small local holiday to commemorate the process.
Regardless, there aren't that many possible values aliens could have. It is hard to come up with something outside basic game theory - you can see how most religions tend to converge on the same practical principles over time, like basic property rights and not causing trouble pointlessly.
I don't see why an intelligent alien species would have similar values to us. It would depend entirely on their social organization so unless they were the exact equivalent of us evolutionarily (omnivorous, sexually dimorphic, social, bipedal, terrestrial, etc.) they would value the lives, property, territory and status of their own kind and other animals very differently.
A race of aquatic arthropods could be mostly solitary, cannibalistic and regard age and size as primary dominance characteristics and their notion of property rights might depend entirely on whether they can eat the owner of said property, though sublimated through some complex set of social rules and protocols. Maybe the CEO of a company only has to offer a single leg to be eaten during a hostile takeover.
I see someone else recently read Children of Strife.
Damn, I really enjoyed that book. Best of the series so far, in my opinion.
Actually I haven't but I'll check it out.
A necessary condition for the emergence of civilization (in its broadest sense, as in the collectively organized reshaping of one's living environment for one's purposes) is a basic level of trust and cooperation.
Humans are not naturally prone to bouts of violence like other species and human societies do not tolerate impulsive violence in adults. Instead, the vast majority of human-on-human violence is deliberate: people plan, carefully and rationally, the killing of their fellow human beings in order to achieve their goals. This is known as 'war'. This is very rare among species, and more violent species cannot form complex societies at scale, despite being also quite smart in some cases (chimps, octopuses).
We even unconsciously internalized this idea to some degree, since most people are comfortable with the idea of militaries existing and being necessary but also agree that solitary murderous psychopaths should be put in prison.
>Humans are not naturally prone to bouts of violence like other species
That... does not check out. There are plenty of violent people, I've met many.
I mean could a race of aquatic arthropods ever organize in scale enough to be a species that can travel light years and invade others? Wouldn't they just eat each other and never have any need to build a community or to colonize space?
We need to have some baseline for what we consider as "intelligent species" in this context and most intelligent species will need to have a system where they can pool their resources together towards something in a sustained social manner. This rules out a lot of social patterns such as beings that are solitary, canibalisitc and hell bent of eating each other.
If you showed me a primate and I didn't have any knowledge of the existence of humans and then asked the same thing of them I'd also have to get creative about how they may evolve to be an intelligent society.
I spent ages trying to find it, but couldn't. Unless I dreamed it.
I read a sci-fi story where the probe lands on Earth, and then teaches us enough science to get our own ships together, and tells us where to go to meet the probe makers. So they don't have to go anywhere and can sit comfortable at home and wait for the aliens to come to them.
I tried to lookup a Star Trek episode of this premise and found a Voyager episode: https://en.wikipedia.org/wiki/Friendship_One_(Star_Trek:_Voy...
This is a likely scenario of misinterpretation between species haha.
Contact?
yeah, similar. Might be it, I guess? meh, apologies for being vague and old.
You might like Blindsight by Peter Watts
There's a fan-made short film/trailer for Blindsight:
https://www.youtube.com/watch?v=VkR2hnXR0SM
Also, "just an AI probe" and "It would be amazing" in the context of Blindsight... <insert mad laughter>.
Charles Stross, Singularity Sky, sort of covers this.
we may have found that AI a while back in roswell, along with some Nitanol foil and berylium "I" beams
It is quite remarkable that the question of life on mars (or not) hasn't been answered conclusively despite a lot of human effort to get an answer.
NASA intentionally completely gave up on trying to answer the Mars life question for multiple decades and only very recently has come back around to the idea of doing life finding missions.
there probably never was any there for a meaningful amount of time, but it's incredibly hard to prove a negative.
It's a touchy subject because scientists are afraid of looking like cranks. Just like cognition in other nonhuman species was historically dismissed because no one wants to be seen as someone who think plants talk to each other
It's because the more important question of "how can I personally profit from this?" usually takes precedence.
lolz
We all came from Mars, don't you know it? There was a series of "extreme weather events" and we had to escape. Now there is some guy dreaming to get back home. /s
[dead]
I see this author has "12 honorary degrees and is an Officer of the Order of Canada". And CBC is Canada's government-funded national public broadcaster.
But it's hard to take them seriously on any particular details given that their article, up for 8+ months (!), mis-describes H.G. Wells' War of the Worlds as a story of the Earth "invaded by benevolent Martians". [emphasis mine]
It's a seminal work of scifi, which popularized the "alien invasion" genre and term "Martians' (both for literal creatures from Mars and also a metonym for any alien visitors/invaders). It's been adapted to film many times. And the Martians in it - with their disintegrating heat-rays & death-clouds, consuming human blood – are far from 'benevolent'.
It was obviously meant to read 'malevolent' and got spell checked to death. That sort of thing happens to everyone, and I'm not sure why you mention the authors credentials like they're a bad thing?
Because honorary degrees are not credentials.
But that's obviously not a reason to treat them as a bad thing. It's also not entirely true ... he was awarded those honors because of the quality of his science journalism.
FWIW, I think @mapontosevenths is wrong to say that @gojomo's mention of the honorary degrees and being an OOC was "like they're a bad thing" ... their "But it's hard ..." indicates a conflict between those "credentials" and the typo that gojomo makes way too much a deal of.
So many people here have no idea how things work and are far more interested in virtue signaling over an error (and making spiteful downvotes) than in correcting it, so we get ignorant and intellectually dishonest rubbish like
> I think readers should take this as an illustrative example of how often people/institutions draped in such quasi-credentials are carelessly wrong on basic things.
and
> how many people had to be asleep at the wheel for the truth-reversing error to get published, & persist for months? Does no one at the CBC – with pride in its work & any familiarity with these topics – read CBC's slop?
I, OTOH, sent them a note and they quickly fixed the article. Errors like this "persist for months" simply because no one takes the time for such a simple action when they encounter an error ... I'm the only person among those who commented here who did so. And no, of course no one at the CBC or anywhere else spends their time rereading their months-old articles to see if some error made its way in.
I just wanted to say thanks for actually taking the time to make the situation better for everyone, rather than complaining.
And thank you ... I really appreciate that.
Because I think readers should take this as an illustrative example of how often people/institutions draped in such quasi-credentials are carelessly wrong on basic things.
Even if some typo of 'malevolent' becoming 'benevolent' was how this error initially created – & I have my doubts! – how many people had to be asleep at the wheel for the truth-reversing error to get published, & persist for months? Does no one at the CBC – with pride in its work & any familiarity with these topics – read CBC's slop?
Someone should look into the author and/or editor.
Probability seems high they are martians trying to whitewash fictional history.
I got so caught up in that phrase I went rereading the plot summary of WOTW to check my memory. After than I had no interest in the article, assuming it had been written by AI.
War of the Worlds is culturally-prominent enough I doubt any commercial AI would make this same mistake (or let the error slip through, if they'd asked the AI to fact-check the article).
Maybe the author mixed it up, with another Martin invasion story called "Two Planets" (https://en.wikipedia.org/wiki/Two_Planets), which was released a bit earlier than War of the Worlds and according to Wikipedia, it "is the earliest known example of the theme of a Beneficial alien invasion".
If someone is interested in "historical" science fiction, I can recommend it.
But nonetheless, if the author is interested in Mars and science fiction, he should be able to keep them apart from another. Maybe an editor wasn't?
I can confidently say that nobody has ever confused The War of the Worlds with The Two Planets.
It's hard to take seriously someone who dismisses the (factually correct) content of a popular science article just because of a typo that has no bearing on that content.
Have you independently checked all the other allegedly "factually correct" info in this article, with other sources that are actually diligent in getting the details right? What's the incremental value of a news source where every detail that you don't already know might be very wrong?
Io credo che possa essere come dici tu ma prima servono le prove
Wrong language?
Italian. Maybe their browser auto translates English to Italian and expects everyone else to have a browser functioning that way (translating any to their native language)?
Mineral that can be only formed by life, or under special conditions when water flows over rock, has been found on Mars, where water had been known to flow over rock.
NASA doesn't want to find life on Mars. They want to find evidence, so that the next probe can be more complex and more expensive than the previous one.
NASA will never send wet microscope to Mars, you know, the kind you used in school to show bacteria in dirty water. As that would instantly prove life on Mars and make ever more expensive probes hard to justify.
I’m curious why you seem to believe that all exploration of Mars would cease as soon as life is discovered there? It would be one of the biggest scientific discoveries of all time and would open up a huge number of possible future missions, for the next few centuries at least. It would also make for good justification for missions to other worlds that could harbor life.
Scientists can string out things. It is a means of securing funding for long periods.
I think there has been evidence of life in the Venusian atmosphere since the 80s and on/in Mars since the 70s.
Weak evidence for life, at best. Which is why exploration continues, to search for stronger evidence. If irrefutable evidence of life were found it would open up many new avenues of exploration and research that would need funding, with strong justification - much stronger justification than currently exists.
I don't think it was weak at all. We got two positive results from the Viking landers and then tried to explain them away. There is a lot of circumstantial evidence, which combined builds up a case.
The public believe we should be looking for cities and skeletons, when in fact we should be looking for extremophiles. It is possible that some of these are due to cross-contamination within the solar system (before human intervention), but that is another matter.
Two positive results that had non-biological explanations and a lack of any other significant evidence. Extreme skepticism is warranted.
They are best thought of as circumstantial evidence, especially when combined with the various other possible indicators we have detected on Mars. Many books I have read over the years talk about the Viking experiments as if they had disproved life, whereas they did no such thing.
However, I think the bulk of life on Mars – if it exists – is probably underground. Conditions there are much less hostile than the immediate surface. Since Viking, we continue to find Earth life in extreme environments including high altitudes and deep underground. Microbes can be much tougher than animals.
The two Viking landers, 6500km apart, had positive results. That would suggest that life is widespread and close to the surface. But the atmosphere of Mars is in chemical equilibrium, which means life can't be widespread and close to the surface because it is not affecting the atmosphere. If life is present on Mars it would have to be deep underground, perhaps in a geothermally heated brine lake, which would be very hard to detect with current technology. The Viking data was probably non-biological, it really isn't strong evidence for life today.
There are questions about methane in the Martian atmosphere. Again, there is some ambiguity as to why.
However, we have found life in some very hostile environments on Earth, notably high up in the atmosphere. Planococcus halocryophilus can exist on Earth at -20' C, well within Martian surface temperature ranges, and is tolerant of very salty water. Microbes need a fraction of the resources we do, and some can exist in very small numbers for long periods before better conditions come along. Surface temperatures on Mars have been observed to go over 20' C during the day in some places which may allow for some warmth to penetrate rock and dust. A very hostile environment, to be sure.
https://www.nature.com/articles/ismej20138
Sending a microscope is easier said than done. Many natural structures can look like bacteria, and vice versa. If there's more complex single celled life then we might see stuff swimming around but that's considered unlikely close to the surface where there's a decent amount of solar and cosmic radiation. If complex life does exist it's probably deep underground or in caves and lava tubes where we can't reach it yet.
The other reason is planetary protection. The best places to send a microscope are low lying areas where there may be brines near the surface. Those specific areas have been designated high on the list of protection sites. Earth microbes are really resilient, so even with intense sterilization procedures we can't be 100% sure. We don't want to contaminate the most valuable scientific find ever, and so we're approaching it carefully.
But I think the first reason I gave is the most significant one. It's technically pretty hard and not definitive. The surface of Mars is probably mostly sterile even if there is life. If it survives, it's probably underground.
I also disagree that NASA would not want to find life. If anything, finding life would make their budget explode. They could suddenly make a strong case for a Europa submersible, a submarine to visit Titan's methane lakes, huge space-based SETI radio telescope arrays, huge space telescopes to try to find more exoplanets and characterize their atmospheres, all kinds of things, since we'd know for a fact there's life out there.
If life emerged in two places in one solar system, we'd know that the universe is teeming with it. Maybe not complex intelligent life -- there's still reasons to think Earth may be kind of special for that. But life, certainly.
There is a lot of abrasive dust on Mars as well, which poses a problem to any microscope.
Luna is abrasive, essentially like shards of non safety glass. The dust on mars is soft, it's been blowing around since before the dinosaurs died off. The main issue with martian dust is electrostatic charge, but that's easier to manage than lunar dust.
What reasons do you think exist that lead you to believe Earth is special for having evolved complex intelligent life?
The Fermi Argument.
That’s actually an argument in support of life existing in many places across the universe.
I don't see how it could be interpreted that way. Please explain.
If they found actual life on Mars the NASA budget would multiply many times, so I don't understand your thinking.
I think the opposite - unless the discovery of life was preceeded or coincidental with the discovery of some other hyper interesting thing (for example, if Martian life has some sort of utility for medicine, maybe) then I think that would be that for Mars exploration missions. Of course there would be many announcements and excited political agreements around "continuing to explore the new frontier" but I think that no more money would appear.
I suspect that NASA knows this full well, as do Mars scientists, and I suspect that they are being very careful to make sure that definitive proof does not appear until they understand all sorts of other stuff about the planet.
But why? Why would there be no money for that but there’s money now when there’s no conclusive evidence of life, past or present, on Mars? It makes no sense.
Because looking for life on mars sells.
"Why are we not spending that money on more social housing?" : Because this is the greatest mystery of our time... (nods all round)
"Why are we doing science?": I don't know and I don't care, cut my taxes! (Cheering and mocking comments about nerds.)
If life were found on Mars then the greatest mystery of our time would be whether life originated at least twice independently, or if we share a common origin. Both of which have significant implications, to put it mildly.
This is where we are at on HN.
Conspiracies that NASA already found alien life and is suppressing it to continue funding.
Or you know the far more likely case:
No one has ever found any evidence of life anywhere and exaggerating tiny findings adjacent to it keep funding flowing.
No it couldn’t be that.
Well, Viking carried an experiment that tried to detect life. Now, the consensus is that it failed, and that the experiment was incapable of creating a useful result given the chemistry of the soil. Some people argue about that, but I am in no way qualified to take part in the debate, so I would back the consensus here.
What is odd is that there hasn't been a single other mission that's carried any experiment that has the objective of creating that result.
If the objective is to find life, why isn't anyone actually looking?
Tell me if what I've said above is in any way factually incorrect.
The Viking results were at worst, inconclusive and at best positive. And yet in both cases we have been led to believe they were negative. They are far from the only pointers to life on Mars either, since we've seen pictures of what look like fossilised stromatolites and algal mats, seasonal methane emissions, and discolorations in seasonal flows & ice.
Even the rusty coloured surface of Mars may be due, in part, to organic oxidisation processes.
We aren't talking about Richard Hoagland style cities here (although that Face on Mars is a lot less easy to explain away that some people claim).
The “face on mars” is an image compression artefact that disappeared as soon as they had high resolution imaging of the area. Seeing it as a face is highly dependent on sympathetic lighting and the right time of day, like lots of similar features on earth eg the “Old Man” of Hoy which I have seen first-hand and you really have to want to see it as a man’s face to do so https://en.wikipedia.org/wiki/Cydonia_(Mars)
I've heard this before and the pareidolia argument. The fact remains that in certain other pictures you still can see the face. There are some other unusual formations near it as well. The only example that comes close is the Badlands Indian in North America.
I've always found it an extremely weird formation. I suppose it has been explained by frost shattering and ancient floods. If an ancient race were to leave sculpture behind, millions of years would obliterate most of it. Some people have said that probes should be sent to Cydonia. I hope they send some kind of flying probes round there, since the geology alone makes it of interest, and landers/orbiters may not get it.
As for the Old Man of Hoy, that is something different. Old Man (or Bodach in Gaelic speaking areas) was used for a lot of natural pillars and stacks, standing stones and phallic formations. Occasionally for mountains. Old Man/Bodach is/was a euphemism for the Devil who was said to have created many of these things, and that goes way back before the Old Man of Hoy.
In Gaelic, it takes on a phallic quality: "Bod" means "penis" and "bodach" means "old man". Orkney was never Gaelic speaking as such, but in Gaelic the euphemism is more obvious. This usage carried over there and the Old Man of Hoy probably gets that name because it is tall and thin. Maybe the Picts had such notions too.
You have to admire the discipline, willpower, and solidarity of all those scientists. Any one of them could prove the existence of life on Mars at any time, win a Nobel Prize, become the the most famous scientist since Einstein, put themselves on the gravy train for life... but they all hold out, keeping their decent, upper-middle class jobs, hiding one of the greatest discoveries in history, so that their colleagues don't have to find potentially slightly less lucrative or interesting jobs. That's dedication!
/S
>>Well, Viking carried an experiment that tried to detect life. Now, the consensus is that it failed, and that the experiment was incapable of creating a useful result given the chemistry of the soil. Some people argue about that, but I am in no way qualified to take part in the debate, so I would back the consensus here.
>>What is odd is that there hasn't been a single other mission that's carried any experiment that has the objective of creating that result.
>>If the objective is to find life, why isn't anyone actually looking?
>>Tell me if what I've said above is in any way factually incorrect.
So... you tell me. Why no experiment? Not one in 50 years?
In the meantime we've learned a lot about the Martian atmosphere, it's climate, it's history, it's geology, the evolution of it's surface. I would argue that if a Viking 3 had flown with a revised kit that produced a definitive signal we wouldn't have got any of that.
This is an odd comment. Any scientist or scientific organisation would love to be the first to discover life on another planet. It would catapult that organisation and individuals involved to legendary status with their discoveries being counted amongst the greatest of humankind. It would be an epoch defining moment. Funding for their work and personal riches would pour in. There would be movies made about it. Their names would be remembered thousands of years into the future.
To imply there would be a conspiracy to cover up such discoveries because you think the opposite would happen is such an odd way to think about things.
Do you really think that all the scientists view NASA as a make work program? That so many people spent years in schools getting advanced degrees and there is no one there who wants to make the most significant discovery in the history of humanity? That nobody wants the instant Nobel prize?
It also doesn't make sense from any kind of financial perspective. The budget for NASA would explode for all kinds of missions. They would have free reign to go wherever and do anything.
The discovery team would instantly create brand new fields of study and career paths, and anyone on the team that discovered life would become experts in the field with unlimited investment opportunities to continue their research.
At least one scientist close to retirement right? That would surely earn them more money: )
What mineral can only be formed by life?
You know what they say, sufficiently advanced geological process is indistinguishable from life.
Coprolites.
Plutonium?
Oklo natural uranium reactor already producted plutonium naturally.
Americium, then.
A little far-fetched..?
> NASA doesn’t want
Citation needed
> NASA will never
Citation needed
Viking 1 & 2 returned positive results in the seventies but these have been played down or hand waved. I think there is good evidence of microbial life in the soil or underground. We should be wary of bringing Martian microbes back to Earth, because they may find our environment too hospitable and end up invasive species.
> We should be wary of bringing Martian microbes back to Earth, because they may find our environment too hospitable and end up invasive species.
They could even already have invaded in the past, and we descended of them[1]. Earth as Mars ancient lifeboat[2].
[1] https://www.bbc.com/news/science-environment-23872765
[2] https://badspacecomics.com/apostles-of-mercy
Yes, that is perfectly possible. There could be some transfer, but there is a scenario where Martian microbes breed on Earth and have no natural controls. An Australia type scenario on a planetary scale.